A paper sheet handling apparatus that handles paper sheets (such as bills) is mounted in, for example, an automatic teller machine (ATM) installed at a financial institute or the like and includes a money deposit/Withdrawal port for a user to deposit or withdraw paper sheets and a conveyance unit for conveying the paper sheets to and from a paper sheet storage container in a safe. The money deposit/withdrawal port of the paper sheet handling apparatus is provided with a photodetector that detects insertion/removal of paper sheets and the user's fingers; and the paper sheet handling apparatus can handle the paper sheets for the purpose of money deposit and withdrawal by controlling the operation to open and close a shutter provided at the money deposit/withdrawal port on the basis of detected information from this photodetector.
Regarding automatic teller machines, some are of an outside wall type which is embedded on a wall of a building, and some are installed inside shops; and external light (particularly, sunlight) may sometimes affect the money deposit/withdrawal port of the paper sheet handling apparatus. Specifically speaking, when the shutter of the money deposit/withdrawal port is left opened and the external light reaches a deepest part of the money deposit/withdrawal port, the photodetector may mistakenly detect the external light and malfunction and the paper sheet handling apparatus may abruptly close the shutter.
Thus, as a means for preventing false detection of the external light, there is a know example in which a light-shielding barrel is connected to a photodetector to enable the photodetector to detect the light emitted from a projector via the light-shielding barrel, while protecting the photodetector with the light-shielding barrel against the external light (for example, PTL 1 and PTL 2).